[Antivirus effect of plasmid co expressing hepatitis B surface antigen and granulocyte macrophage-colony stimulating factor].

OBJECTIVE

To investigate whether GM-CSF can enhance the antiviral effect of HBsAg DNA vaccine.

METHODS

Divided animals into 8 groups. Group A: pcDNA3.1-S 100microg; Group B: pcDNA3.1-GM-CSF-S 100microg; Group C: pcDNA3.1-S-GM-CSF 100microg; Group D: pcDNA3.1-S 50microg + pcDNA3.1-GM-CSF 50microg; Group E: pcDNA3.1-GM-CSF 100microg; Group F: recombinant HBsAg vaccine 1microg; Group G: pcDNA3.1,100microg; Group H: PBS 100microl. Serum HBsAg level and concentration of IL-2, IL-4 and IFN-gamma were examined using commercial ELISA kit. The [3H] thymidine incorporation into DNA of Spleen cells was measured; HBsAg expression of hepatocytes from HBV-transgenic mice was assessed using immunohistochemical analysis.

RESULTS

Serum HBsAg level was lower and concentration of IL-2, IFN-gamma and SI was higher in mice immunized with pcDNA3.1-GM-CSF-S than those from mice immunized with pcDNA3.1-S and other groups (F=11.262, P<0.01, F=8.147, P<0.01, F=62.275, P<0.01, F=116.28, P<0.01. Less Hepatic HBsAg expression and decline of pcDNA3.1-GM-CSF-S of mice immunized with pcDNA3 were observed in comparison with control groups (F=41.439, P<0.01). Liver histological analysis showed no evidence of necrosis or inflammation in various groups.

CONCLUSION

The plasmid co expressing GM-CSF and HBsAg could improve HBsAg-specific humoral and cellular immune responses induced by plasmid encoding HBsAg alone and enhance HBsAg DNA vaccine antivirus effect.